Share

IIR document

Heat transfer and flow characteristics of condensing flow in a quadrilobed tube.

Number: pap. n. 907

Author(s) : ASANO T., ASANO H., HARA H.

Summary

A double tube heat exchanger is usually used in heat pump water heater to obtain large water temperature rise. Condensing heat transfer coefficient decreases with decreasing vapor quality due to increase in liquid film thickness. Non-circular small diameter tube has possibility to improve the condensing heat transfer, because liquid film thickness becomes non-uniform by surface tension. This study deals with condensing heat transfer of HFC-134a in quadrilobed tube with the crosssection consisting of four leaves and core. Condensing heat transfer and pressure loss in horizontal tubes were experimentally evaluated. From the results, it was confirmed that deterioration in the condensing heat transfer coefficient was suppressed under moderate wetness for the low refrigerant mass flux less than 300 kg×m-2×s-1, because condensed liquid might be accumulated in the narrow part by the surface tension. However, pressure loss increased due to maldistribution of refrigerant flow.

Available documents

Format PDF

Pages: 8

Available

  • Public price

    20 €

  • Member price*

    Free

* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).

Details

  • Original title: Heat transfer and flow characteristics of condensing flow in a quadrilobed tube.
  • Record ID : 30026051
  • Languages: English
  • Source: Proceedings of the 25th IIR International Congress of Refrigeration: Montréal , Canada, August 24-30, 2019.
  • Publication date: 2019/08/24
  • DOI: http://dx.doi.org/10.18462/iir.icr.2019.0907

Links


See other articles from the proceedings (632)
See the conference proceedings

Indexing